Photolithographic Hole-Transport Layer Derived from Electrochemical Deposition of Oligo(5-vinyl-2-nitrobenzyl triphenylamine-4-carboxylate)

Abstract

Electrochemically deposited layer (EDL) prepared from electropolymerization of oligo(5-vinyl-2nitrobenzyl triphenylamine-4-carboxylate) on conductive indium tin oxide glass (ITO) showed photolithographic properties as well as good hole-injection and transport properties. Under the optimized conditions, the polymeric light-emitting device (PLED) of ITO/EDL/polyvinylcarbazole(PVK)-Ir(PPy) 3 -[2-biphenylyl-5-(4′-tert-butylphenyl)oxadiazole] (PBD)/Mg-Ag had a turn-on voltage of 13.5 V (100 cd/m 2 ) with a maximum brightness of 9100 cd/m 2 , and the current efficiency of 10.3 cd/A. When the EDL was exposed to UV light (365 nm) through a patterned photomask and developed in CH 2 Cl 2 , a positive image was obtained. After irradiation for 8 min through a band-pass filter (17 mW/cm 2 ) by a Xeon lamp, the EDL became soluble and could be depleted completely in CH 2 Cl 2 . Patterned PLED device was also fabricated by this technique.

Synthesis and self‐assembly of diblock copolymers bearing 2‐nitrobenzyl photocleavable side groups

“…Initially developed as photolabile protecting groups for carboxylic acid and amine groups in organic and peptide synthesis,35, 36 they were progressively introduced in material science since the early 80s. Typically, they were incorporated in polymers for the production of photoresist materials37–48 and, more recently, in block copolymers for applications such as light‐triggered drug delivery and nanoporous materials 21, 10, 20, 49…”

Cross‐Linked Multifunctional Conjugated Polymers Prepared by In Situ Electrochemical Deposition for a Highly‐Efficient Blue‐Emitting and Electron‐Transport Layer

“…The PFCzPO ED film has a RMS roughness of 3.64 nm, which is analogous to the film morphology obtained after spin‐coating from solution. The morphology of ED films is greatly improved compared to previously reported polymer ED films 8–12. We point out that this is the first ED film using a CP precursor that exhibits such a smooth morphology.…”

“…There are only a few reports about ED that use CPs as precursors 8–12. However, resultant ED films showed a very rough morphology and weak fluorescence, which makes it difficult to use them for the application in devices.…”

“…One important factor to obtain a high‐quality ED film is ED under low potential, which benefits the doping/dedoping process. The previous reported ED of CPs precursors usually required a high oxidation potential applied during the ED process because the CPs precursors with low solubility showed low electroactivity 8–12. But ED under a very high oxidation potential will lead to more structural defects and high electrolyte doping level, which will obviously affect the optoelectronic functions, especially the luminescent properties of ED films.…”

Electrochromism in Electropolymerized Films of Pyrene-Triphenylamine Derivatives

“…A large number of electropolymerized films have been prepared from monomers functionalized with thiophene or carbazole derivatives [22,23,24,25,26,27,28]. In addition, triphenylamine groups have been used as polymerizable units to prepare thin films of organic and metal complexes by electropolymerization [29,30,31,32]. Triphenylamine can be electrochemically oxidized into aminium cation radical, which acts as the key intermediate to form polymeric structures connected by tetraphenylbenzidine bridges (Figure 1) [29,30,31,32].…”